The concept of dental implants emerged in the 70-ies. Therefore, well-planned implant treatment is considered to be a reliable and safe method nowadays ensuring long-term results. Though dental implants cannot replace a natural and healthy tooth, still it becomes a perfect choice, when the prognosis of a natural tooth is bad. Dental implants have worse protection against infection, therefore especially thorough planning and a very good care is needed for implant cases.
- Disadvantages of a traditional prosthesis
Dental implants have fundamentally altered the approach to the treatment of tooth loss. Teeth with large crown defects, root canal and periodontal unfavourable prognosis were treated by complicated, time-consuming and uncertain long-term prognosis treatment methods. In the absence of teeth partial fixed prostheses (bridges) were made, which required neighbouring teeth to be prepared. It was difficult to clean the area below the bridge and susceptibility to tooth decay and periodontal disease increased (Picture 2.). Dental esthetics were often inadequate, and prognosis was lower as compared to dental crowns. Larger or free-end saddle dental arch defects and edentulous jaws were traditionally restored with removable prostheses. These prostheses were less stable and non-aesthetic. Patient satisfaction due to low masticatory efficiency and unacceptable estetics was low. Due to progressive edentulous ridge resorption, such treatment results deteriorated over time. For the same reasons, the use of removable full dentures was particularly embarrassing.
- Dental implants opportunities
The disadvantages of conventional fixed and removable prostheses can often be avoided with treatment of dental implants. Teeth with an unfavourable prognosis can be removed and replaced by dental implants – in order to avoid complex and lengthy treatment with uncertain prognosis. Bounded by teeth defects can be restored without grinding of neighbouring teeth and prevent bone resorption (Picture 3.). If there are free-end edentulous defects – removable prostheses resting on soft tissues can be avoided. Edentulous jaws can also be restored with fixed or removable prostheses on implants.
- Bone augmentation procedures
Wide application of implants is limited by insufficient quantity and quality of the bone in the area of removed or missing teeth, unfavourable condition of the soft tissues etc. In case of insufficient quantity of bone, various bone augmentation techniques using autologous, allogenic or synthetic bone substitutes are being used. Bone regeneration techniques may be used after the removal of teeth in order to accelerate wound healing and reduce bone resorption. The guided bone regeneration (GBR) and sinus lift surgery is the most commonly used in clinical practice. GBR procedure is used when there is a narrow alveolar ridge and one side of the dental implant may stay outside the contour of the bone. In this case, it is needed to add a bone substitute material to this side (Picture 4.). This procedure, if possible, can be performed at the time of dental placement, and if the bone deficiency is high, two separate phases of surgical operation may be needed. Bone defects of lateral or vertical direction can be restored using other methods – splitting of alveolar ridge and similar. Sinus lift surgery may be needed in the upper jaw, in case the sinus wall is in low position and there is not enough bone height to place the implant of appropriate length. In this case, raising the sinus floor membrane is performed through a window in a lateral sinus wall, a bone substitute material is introduced to the resulting space and then implant is placed (Picture 5). Where the missing bone height is up to 3 mm, it is possible to perform minimally invasive closed sinus lift surgery, without making window in lateral sinus wall. Careful clinical assessment of the situation and planning of treatment allow reducing the need for bone augmentation and to restore chewing, speech, and aesthetic functions to the maximum with the help of implants.
- Implants treatment course
Dental implant placement is a surgical procedure, therefore a detailed examination of the patient shall be carried out prior to the surgery. Absolute contraindications for dental implants are very rare. In addition to the general health of the patient, the status of bite and neighbouring teeth is being evaluated; radiological assessment is carried out to assess the quantity and quality of bone. In many cases, panoramic X-ray image is sufficient. In case of larger bone defects and unclear anatomy, it is needed to objectively assess the amount of bone using 3D CBCT scan (Picture 7.). Based on the examination results number, type of implants, and their location is selected.
In vast majority of dental implant surgery cases local anesthesia is sufficient. For precise implant position various types of surgical and radiological guides can be used (custom made acrylic splints with marked implant positions). Implant surgery is very well tolerated procedure, as many patients on the next day do not need any pain-killers. In post-surgical period the course of antibiotics can be prescribed.
Restoration of placed implants is usually performed 1,5 months after surgery. Implant loading can be postponed if bone augmentation procedures were used. Implant with good primary stability and meeting other requirements can be loaded even right after implant surgery (immediate restoration or immediate loading). In this case patient missing a tooth, gets esthetic prosthesis on dental implants in one visit.
Dental implant placement and bone augmentation procedures will be delivered to you by our experienced prosthodontist Assoc. Prof. V. Rutkūnas DDS, PhD.